Electrical switching apparatus



Patented Apr. 7, 1931 UNITED STATE earn-"Ff P F E HUMPHREYS o. SIEGMUNID, or wns'r ORANGE, ivnwannsn essrenon To BELLTELE rnonn LABORATORIES, rnconnonamnmoravnw YORK, n.1, A CORPORATION. or

NEW .YORK

ELECTRICAL swrrcnrne Armaments;

Amniemm m November 2?, 192 8. Seria1'No. 322,2 72.

, This invention relates'to electrical appa ratus and more particularly to contactmembers for usein such apparatus.

In contact springs of the type used in re lays, for example,the springs are generallyassembled'in a pile-up arrangement with superposedinsulatlng spacer members and the whole held in an adpisted position on a the manufacture of the contact of this invention,the non-precious and the precious metals are preferably formed into strips and welded in superposed arrangement The cross-section of the strips, however, is such that the teceive apron in'the sparkingjregion otthe contact. The strip of bi-metalthus formed 7 no precious metal partly covers the sides ofthev non-precious metal in order to form a pro-.

, common supporting member by a number of m screws. While the clearance holes. in the springs through which the fastening screws thread, are maintained at accurate alignment with respect to thelongitudinal axis of'the springs and at accuratelyspaced distances 15 from the central axis of the contactpoints,

' due to the deviation ofthe springs relative to each other or their relative displacements uponftheir assembly on the support, it was necessary to make at least one of the contact elements of a much greater diameter where 1 circular shaped contacts are used, or .each ota .much greater length where cross conmay then bewelded to a supporting member and out therequired lengthin a subsequent operation. i i j i q Other features of the invention andadvantages will appear from the following descrip tion and by the claims appended thereto, reference being had to the accompanying drawings, in which, j i i Fig. 1 is an enlarged viewof switch springs equipped. with' contacts made according to this invention, one of the springs being shownwith portions cut away,

Fig.2is a side vlew of the switchsprings tactsare used, in order tov assure registration between associated contacts with consequent aswastingof a considerable amountv of contact or precious metal. a

Applicant has discovered thatthe registering areas of springs thus assembled ,were deviatedin two directions atright angles to. each other, that is, laterally and longitudinally, and that themaximum deviation occurred at right angles with respect to'the longitudinal axis of the springs, thus deviating the contacts'within a parallelogram area of. 5 contact registration. Applicant further discovered that by disposing the contacts with their; longitudinal axis parallel to two adjacent sidesof the parallelogram bounding the maximum deviation of the springs, and

40 of the same length as that of the parellelogram sides, any point within its boundary may be covered by these contacts while eflecting a considerable saving of precious metal for the contacts.

Applicant further discovered that amaximum of eflicient operations is obtained and the greatest amount of precious metal saved by using non-precious metal for the body portion of the contact and using precious metal 50 for the efiective portion of the contact. In

ta d shown in Fig. 1 showing the springs in an' assembled position on their supporting brack- I Figi s is a diagram showing the'extent of deviation inthe registration of the contacts.

According to this invention, switchsprings 10,, and ll shown in Figs. 1 and 2 are each provided with a contact member. 12 and 13 which be secured in adjusted'position thereon as by weldingor-in any other. well known manner. y Contact .12 is disposed substantially-at right angles withrespect to the longitudinal axis of spring 10 and its associated contact 13 in line parallel to that of the longitudinal axis of the supporting spring 11, these contacts,

however, being so disposed relative to each I other that upon the accurate alignment of I springs 10 and 11 the area of registration is substantially atthe middle point of these 1 contacts. I

relatively large number of switch spring units 100 In Fig.- 3 each square representsin an en larged scale, one position of the cooperative 95 and the arrow 15 in Fig. 3 indicates the relative position of the parallelogram with respect to the length of the springs. In Fig. 3 the fine screened group 0]": squares shows that of over of the springs tested the contacts 12 and 13 register within this area; the circle of vertically lined squares shows that over 90% of the contacts register within the area bounded by this circle; the circle of coarse screened squares shows that over 99% of the contacts registerwithin this area and the circle of horizontally lined squares shows that all the contacts tested registered within the area bounded by the inscribed parallelogram.

According to a feature of this invention contacts 12 and 13 are'each made of a length corresponding to that of two adjacent sides of the parallelogram, above referred to. Contact 13, the length ofwhich corresponds to the lengthot side 16, is disposed on the longitudinal axis of spring 11 and contact 12, which corresponds to that of side 17, is disosed at ri 'ht an 'leswith res ect to that of the longitudinal axis of the supporting spring 10 and therefore at right angles with respect to its associated contact 13, thus per-..

13 in proportion to the area bounded'by the sides of the inscribed in Fig. 3. I

What is claimed is 1. In electrical switching apparatus, associated switching members secured at one end to a common supporting member, said members having a permissible non-alignment or sweep with respect to each other representing a rectangular area, Contact bars of different length mounted in angular relation on the free ends of said members, each of said contact bars extending in a line parallel with respect to the boundary lines of said area.v I

2. In electrical switching apparatus, a pair of associated switching members carrying contacts, said switching members having a permissible relative non-alignment or sweep and said contacts having a dimension parallelogram shown bearing a definite. relation to the extent of the non-alignment of said switching members.

3. In electrical switching apparatus, a pair of associated switching members carrymg contact elements, said switching 111G111:

bers. having lateral and longitudinal displacements relative to each other and said contacts having a linear dimension bearing a definite relation to the extent of the lateral and longitudinal displacements of. said switching members.

e. In electrical switching apparatus, a pair of associated switching members each carrying a contact element, said switching elements having lateral and longitudinal displacements relativeto each other and one of said contacts having a linear dimension bearing a definite relation to the extent 01.

the lateral displacement and the other contact having a linear displacement bearing a definite relation to the extent of the longitudinal displacement of said switching members. 7

5. In electrical switching apparatus, a pair of associated switching members carryin contacts disposed at right angles to each other, said switching members having lateral and longitudinal displacements relative to each other and each of said contacts hav ing a linear dimension bearing a definite relation tothe extent of the lateral and longitudinal displacements of said switching members.

tiln electrical switching apparatus, a pair of associated switching members carrying contacts, said switching members having an inherent lateral and longitudinal displacement relative to each other and. each' of said contacts being of a length no greater than the maximum displacement of said switching members.

7. In electrical switching apparatus, a

pair of associated switching members" havln'g an inherent lateral and longitudinal displacement, the longitudinal displacement being of a greater'magnitude'than the lateral displacement and a. contact for each switching member of said pair, said contacts being of different lengths, the longer contact being'positioned on its, respective switching members in alignment withthe longitudinal lXlSO1iISELlCl switching member and'the'shorter contact belng positioned on its respective switching member at rightangles to} the longitudinal axis thereof.

In witness whereof, I hereunto subscribe my name this 26th day of November, 1928.

HUMPHREYS O. SIEGMUND 

